NFS: Fix old dentry rehash after move

NFS: Fix old dentry rehash after move

Now that nfs_rename()'s d_move has moved within the RPC task's rpc_call_done
callback, rehashing new_dentry will actually rehash the old dentry's name
in nfs_rename().  d_move() is going to rehash the new dentry for us anyway,
so doing it again here is unnecessary.

Reported-by: Chuck Lever <[email protected]>
Fixes: 920b4530fb80 ("NFS: nfs_rename() handle -ERESTARTSYS dentry left behind")
Signed-off-by: Benjamin Coddington <[email protected]>
Tested-by: Chuck Lever <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>